Investments - Summary of Gross Realized Gains/(Losses) and the Proceeds from the Sales of Available-for-Sale Securities (Detail) - Available-for-sale Securities [Member] - USD ($) $ in Millions |
12 Months Ended | ||
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Dec. 31, 2021 |
Dec. 31, 2020 |
Dec. 31, 2019 |
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| Debt Securities, Available-for-sale [Line Items] | |||
| Gross realized gains | $ 206 | $ 319 | $ 181 |
| Gross realized losses | (19) | 0 | 0 |
| Gains/(losses) | 187 | 319 | 181 |
| Proceeds from sales | $ 24,882 | $ 4,489 | $ 9,580 |
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- Definition Amount of realized gain on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of realized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of cash inflow from sale of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Details
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